Published May 26, 2013 at 500 × 375 in USGS Study Confirms U.S. Amphibian Populations Declining at Precipitous Rates A Sierra Nevada yellow-legged frog (Rana sierrae) scans the landscape in Yosemite National Park. Location: Yosemite National Park, CA, USA. Image credit: Devin Edmonds, USGS (Visited 12 times, 1 visits today)